The Dixon case turns into an episode of CSI-Target

The last time I visited the Baltimore courtroom where Mayor Sheila Dixon is on trial, it was for a homicide case, and a medical examiner was among the many witnesses. This time, the alleged crime is theft and, instead of a medical examiner, the state calls to the witness chair the "asset protection manager" for a major retail chain.

His name is Frank Walborn, and he shows up in wrinkled white shirt and khaki pants, cell phone on his belt, with a 5 o'clock shadow at 10 a.m. Call him "CSI-Target."

Mr. Walborn is an investigator from the sprawling retail frontier, trained in spotting fraud and theft, practiced in the art of tracing purchases with gift cards. Instead of crime-scene photographs, he comes to court with long, white ribbons of paper receipts bearing hundreds of little black numbers generated by his company's retail computer system -- the entrails of the mayor's alleged crimes. He speaks in the monotone of the forensic scientist, referring to receipts projected on the screen behind him, explaining what all the numbers mean, including this one: $1.77.

More on that in a moment.

First, a little background.

The state's case against the mayor, or what's left of it after the judge dismissed two charges on Tuesday, turns on convincing the jury that she took gift cards intended for the needy -- some from a batch purchased in December 2005 by one of the city's most ambitious developers, Patrick Turner, and some from the city's 2007 Holly Trolley Tour. That's the alleged theft -- cards intended for "the children of Baltimore," in Turner's words, supposedly purloined for personal use by the mayor of Baltimore.

Prosecutors need to prove that Ms. Dixon kept or used the cards to buy stuff.

That's why they call Mr. Walborn into the second-floor courtroom on Monday.

One thinks: In the old days, when everyone used cash, such a thing -- a businessman's "donation" to the needy ending up in the hands of an elected official -- would be nearly impossible to prove. These days, with everything digitized and serialized and bar-coded, all transactions would seemingly be a cinch to track.But this isn't necessarily so. Bestowed with enough gift cards, a person can walk into a Target and purchase all kinds of things and leave not a trace -- if the gift cards cover the full purchase amount.

And that's what happened on the afternoon of Jan. 29, 2006, a little more than a month after Mr. Turner bought $500 worth of gift cards at the Target in Pikesville for "the children of Baltimore."